Keywords:
Neuroradiology brain, CNS, MR, MR-Diffusion/Perfusion, Diagnostic procedure, Comparative studies, Inflammation
Authors:
M. Kumar1, R. JAMWAL2, V. Krishnan3; 1New Delhi/IN, 2NEW DELHI, DELHI/IN, 3New Delhi, Tamil Nadu/IN
DOI:
10.26044/ecr2019/C-0888
Aims and objectives
The term demyelination denotes loss of myelin with relative preservation of axons.
This results from diseases that either directly damage the myelin sheaths or damage the cells that form them.
Technological advances in recent years have dramatically improved our understanding of these diseases.
Magnetic Resonance Imaging (MRI) has become a critically important tool in the diagnosis and differentiation of different demyelinating disorders.
In this study,
we have focused on the three major inflammatory demyelinating diseases of the brain,
namely Multiple Sclerosis (MS),
Acute Disseminated Encephalomyelitis (ADEM) and Neuromyelitis Optica (NMO).
The revised diagnostic criteria for these diseases are based predominantly on imaging findings and have considerably reduced dependence on complicated clinical and laboratory tests [1-4].
Diagnosis of inflammatory demyelinating diseases was previously purely based on clinical and pathological tests which often resulted in late and inaccurate diagnosis,
leading to significant disability and morbidity for the patient.
In the current scenario however,
the increasing role played by imaging modalities have significantly improved outcomes.
Disease activity on imaging has traditionally been based on contrast enhancement of the lesions [5].
However,
the administration of gadolinium based contrast agents necessary for this procedure is not always possible due to various comorbidities that the patient may suffer from,
such as chronic kidney disease or contrast allergy.
Diffusion Weighted Imaging (DWI) may potentially play a role in identifying disease activity in such cases without the need for intravenous administration of contrast,
as predicted by a few previous studies [6-8].
In this background,
we have attempted to evaluate the role of DWI as a surrogate marker of disease activity in various inflammatory demyelinating diseases of the brain.